Back Glass Re-Seal Abort!

The rustout in those photos was caused by a cheap replacement vinyl top that was poorly preped and installed.
The original tops dont have that particular kind of backing and the vinyl was heavier and much better quality.
What you have there is a combination of California sun drying/ cracking a low grade vinyl and a nonwoven dacron backing that wicks/ holds water.
I'm not saying that factory tops dont deteriorate with age. The woven back fibers do get weak and tears easily once started. What your seeing there was not the factory's fault or even a fair comparison to how the originals normally age.
To the OP I wouldn't be very worried about the Ohio sun destroying your roof metal like that in the photos.
That was neglect more than any other factor.